Find your own path...
Start from where you already are: if you like the Miles Davis album look into more from the same era... Miles Smiles and Sorcerer are both quite good.
If you like A Love Supreme, everyone who played on that record released bunches of albums of their own (McCoy Tyner is my fave of the quartet other than 'Trane) The players on Blue Trane are also superstars in their own right and have a wealth of great material to sample... Lee Morgan's Sidewinder and Paul Chambers' Bass on Top are both cannons of the genre...
Eva Cassidy didn't put out too many albums (unfortunately), but most of what she did put out were covers of classics... find the original or seminal versions of the songs of hers you like...
You're on the right track with what you have, don't look for a list from someone else, use what you already like as a jumping off point and go from there...
Have fun!
+1 to ElPee.
I would suggest to firstly establish which instruments move you the most. Brass? Piano? Bass?
From there, begin to follow the players who are playing those on the albums you have. So if piano is your thing, have a look at McCoy Tyner, Bill Evans, Wynton Kelly, etc. etc.
Once you have found albums under their leadership, start your trip and continue this way.
I could rhyme off countless albums and players, but I will just drop the names of some players I am spinning alot of lately...
Curtis Amy, Paul Bryant, Curtis Fuller, Teddy Edwards, Booker Little and Gigi Gryce...
I have also been tracking albums from the Jazzland and VeeJay imprints.
Aside from that, Woody Shaw was sent to Earth to inform the human race about music that wasn't to be known for another 50 years. I suppose he travelled through time, but I can't be certain. Stepping Stones: Live At The Village Vanguard is one of the greatest examples of the sheer power of jazz, transcendant as A Love Supreme was.